/*******************************************************************************
 * Copyright 2014 United States Government as represented by the
 * Administrator of the National Aeronautics and Space Administration.
 * All Rights Reserved.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ******************************************************************************/
package gov.nasa.ensemble.common.ui;

import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Widget;

/**
 * A runnable which gets executed in a Display thread. 
 */
public abstract class DisplayRunnable implements Runnable {
	private Widget widget;
	
	/**
	 * Constructs a DisplayRunnable to be run on the default Display.
	 */
	public DisplayRunnable() {
		this(Display.getDefault().getActiveShell());
	}
	
	/**
	 * Constructs a DisplayRunnable to be run on the given widget's Display.
	 */
	public DisplayRunnable(Widget widget) {
		this.widget = widget;
	}

	@Override
	public final void run() {
		WidgetUtils.runInDisplayThread(widget, new Runnable() {
			@Override
			public void run() {
				runInDisplay();
			}
		});
	}
	
	/**
	 * Fill in this method with the action you wish to be performed in the display thread.
	 */
	public abstract void runInDisplay();
}
